Here is a list of, in the United Kingdom, the Crown Dependencies, and British Overseas Territories, schools which only admit boys, or those which only admit boys at certain levels/years/grades, or those which follow the Diamond Schools model (separating students by gender at points).
England Bedfordshire Bedford School, Bedford Challney High School for Boys, Luton Berkshire Desborough College, Maidenhead Eton College, Eton Ludgrove School, Wokingham Papplewick School, Ascot Reading School, Reading Sunningdale School, Sunningdale The Windsor Boys' School, Windsor Bristol Queen Elizabeth's Hospital, Clifton
Buckinghamshire Aylesbury Grammar School, Aylesbury Caldicott School, Farnham Royal Dr Challoner's Grammar School, Amersham John Hampden Grammar School, High Wycombe
Cheshire Sandbach School, Sandbach
Devon Devonport High School for Boys, Plymouth Torquay Boys' Grammar School, Torquay
Dorset Bournemouth School, Charminster Poole Grammar School, Poole Sherborne School, Sherborne
Bournemouth Avonbourne Boys' Academy Winton Academy
East Yorkshire Beverley Grammar School, Beverley
Essex New Hall School Boys' Senior School, Boreham Southend High School for Boys, Prittlewell
Westcliff-on-Sea St Thomas More High School Westcliff High School for Boys
Gloucestershire Marling School, Stroud Sir Thomas Rich's School, Longlevens
Greater London Beths Grammar School, Bexley Brondesbury College The Campion School, Hornchurch Carshalton Boys Sports College, Carshalton Central Foundation Boys' School, Islington City of London School, London Coombe Boys' School, New Malden Darul Hadis Latifiah, Bethnal Green Darul Uloom London, Chislehurst Eaton House Belgravia Pre-Prep and Prep, Belgravia Eaton House The Manor Pre-Prep and Prep, Wandsworth Enfield Grammar School, Enfield Town Ernest Bevin Academy, Tooting Finchley Catholic High School, North Finchley Forest Hill School, Forest Hill Gunnersbury Boys' School, Brentford The Hall School, Belsize Park Hampton School, Hampton Harris Boys' Academy East Dulwich, Peckham Harrow School, Harrow on the Hill Ilford County High School, Barkingside Isleworth and Syon School, Isleworth The John Fisher School, Peaks Hill King's House School, Richmond Langley Park School for Boys, Beckenham London Oratory School Marylebone Academy, Marylebone Norlington School, Leyton Pardes House Grammar School, Finchley Queen Elizabeth's School, Barnet Ravens Wood School, Keston Royal Liberty School, Gidea Park Rutlish School, Merton Park Salvatorian College, Wealdstone St Aloysius' College, Highgate St Bonaventure's, Forest Gate St Columba's Catholic Boys' School, Bexleyheath St Ignatius College, Enfield St Joseph's College, Upper Norwood St Olave's Grammar School, Orpington St Thomas the Apostle College, Nunhead Sussex House School, Chelsea Tawhid Boys School Torah Temimah Primary School, Dollis Hill Tower House School, East Sheen Trinity School of John Whitgift, Shirley Park (becoming co-ed from Sept 2027) University College School, Frognal Wallington County Grammar School, Wallington Wetherby School, Notting Hill/Kensington/Marylebone Whitgift School, South Croydon William Ellis School, Gospel Oak Woolwich Polytechnic School for Boys, Thamesmead
Barnes St Paul's Juniors St Paul's School
Brent Brondesbury College Newman Catholic College
Dulwich Dulwich College Dulwich Prep & Senior
Hampstead Hereward House School St Anthony's School
Kingston upon Thames Rokeby School Tiffin School
Surbiton Shrewsbury House School Southborough High School
Sutton Homefield Preparatory School Sutton Grammar School Wilson's School
Westminster Arnold House School Westminster Abbey Choir School Westminster Cathedral Choir School Westminster City School Westminster School (becoming co-ed from Sept 2028) Westminster Under School (becoming co-ed from Sept 2026)
Wimbledon King's College School (becoming co-ed from Sept 2033) Wimbledon College
Greater Manchester Altrincham Grammar School for Boys, Altrincham Audenshaw School, Audenshaw Bolton School Single Sex Junior, Senior, and Sixth Form schools Burnage Academy for Boys, Burnage Bury Grammar School, Bury Darul Hadis Latifiah Northwest, Oldham Darul Uloom Bolton, Bolton Manchester Grammar School, Manchester Manchester Mesivta School, Prestwich St Ambrose College, Hale Barns Wellacre Academy, Flixton West Hill School, Staybridge
Hampshire Horris Hill School, Newtown Lakeside School, Chandler's Ford Salesian College, Farnborough
Winchester The Pilgrims' School Winchester College, Winchester
Hertfordshire Berkhamsted School, Berkhamsted (separate Boys' Senior School) The Bishop's Stortford High School, Bishop's Stortford Haberdashers' Boys' School, Elstree Hitchin Boys' School, Hitchin Merchant Taylors' School, Three Rivers Richard Hale School, Hertford Verulam School, St Albans Watford Grammar School for Boys, Watford
Kent Borden Grammar School, Sittingbourne Dartford Grammar School, Dartford Dover Grammar School for Boys, Dover Greenacre Academy, Walderslade The Harvey Grammar School, Folkestone The Howard School, Rainham The Judd School, Tonbridge Northfleet Technology College, Northfleet Simon Langton Grammar School for Boys, Canterbury Sir Joseph Williamson's Mathematical School, Rochester Tonbridge School, Tonbridge Wilmington Grammar School for Boys, Wilmington
Maidstone Maidstone Grammar School Oakwood Park Grammar School
Tunbridge Wells The Skinners' School Tunbridge Wells Grammar School for Boys
Lancashire Hutton Grammar School, Hutton Lancaster Royal Grammar School, Lancaster
Blackburn Jamiatul Ilm Wal Huda Tauheedul Islam Boys' High School
Leicestershire Loughborough Grammar School, Loughborough
Lincolnshire Boston Grammar School, Boston The King's School, Grantham Spalding Grammar School, Spalding
Merseyside Birkdale High School, Southport Calday Grange Grammar School, West Kirby St Anselm's College, Birkenhead Wirral Grammar School for Boys, Bebington
Liverpool Cardinal Heenan Catholic High School St Francis Xavier's College St Margaret's Church of England Academy
Norfolk Bure Park Specialist Academy, Great Yarmouth North Yorkshire Ermysted's Grammar School, Skipton Northamptonshire Northampton School for Boys, Northampton Oxfordshire Radley College, Radley St Birinus School, Didcot Summer Fields School, Summertown Swalcliffe Park School, Swalcliffe Oxford Christ Church Cathedral School, Oxford Magdalen College School (becoming co-ed from Sept 2030) New College School
Somerset Beechen Cliff School, Bath Surrey Glyn School, Ewell More House School, Frensham Reed's School, Cobham Richard Challoner School, Kingston upon Thames Royal Grammar School, Guildford (becoming co-ed from Sept 2027) St James Independent Schools Senior Boys' School, Ashford (becoming co-ed from Sept 2027)
Tyne and Wear St Aidan's Catholic Academy, Ashbrooke
Newcastle-upon-Tyne Newcastle School for Boys St Cuthbert's High School
Warwickshire King Edward VI School, Stratford-upon-Avon Lawrence Sheriff School, Rugby Warwick School for Boys, Warwick
West Midlands Birmingham King Edward VI Aston School King Edward VI Camp Hill School for Boys King Edward VI Handsworth Grammar School for Boys King Edward's School Lordswood Boys' School Turves Green Boys' School Wheelers Lane Technology College
West Yorkshire Queen Elizabeth Grammar School, Wakefield Upper Batley High School, Batley
Wiltshire Bishop Wordsworth's School, Salisbury
Former Became coeducational Abbotsholme School, Rocester became coed in 1969. Aldwickbury School, Harpenden became coed in 2025. Archbishop Tenison's School, Lambeth became coed in 1961 and closed in 2023. Bellemoor School, Southampton became the coed Upper Shirley High School in 2008. Blewcoat School, Westminster became coed in 1714 and closed in 1926. Cambridgeshire High School for Boys, Cambridge became the coed Hills Road Sixth Form College in 1974. Charterhouse School, Godalming became coed in 2017. Cheltenham College, Cheltenham became coed in 1969. The Crypt School, Podsmead became coed in 2018. Culverhay School, Bath became the coed Bath Community Academy in 2012, which closed in 2018. Cray Valley Technical School, St. Paul's Cray, became the coed Kemnal Technology College in 1974. Christ's College, Finchley became coed in 2018. Derby Grammar School, Littleover became coed in 2007. Derby School, Derby became coed in 1972 and closed in 1989. Durston House, Ealing became coed in 2023. Elmhurst School, South Croydon became coed in 2024. Eltham College, Mottingham became coed in 2024. The Forest School, Horsham, Horsham became coed in 2021. The Forest School, Winnersh, Winnersh became coed in 2024. Foxwood School, Leeds became coed in 1971. Gordon's School, West End became coed in 1990. Hayesbrook School, Tonbridge became the coed Leigh Academy Tonbridge in 2023. Hull Trinity House Academy, Kingston upon Hull became coed in 2022. John Lyon School, Harrow on the Hill became coed in 2021. The Mall School, Twickenham became coed in 2023. Marlborough Royal Free Grammar School, Marlborough became coed in 1906 and closed in 1975. Norwich High School for Boys, Norwich became the coed Langley School in the 1940s. Oakham School, Oakham became coed in 1971. Old Swinford Hospital, Stourbridge became coed in 2021. Pierrepont School, Frensham became coed in 1983 and closed in 1993. Plymouth Grammar School, Plymouth became coed in the 1900s and closed in 1937. Reading Blue Coat School, Sonning was originally a boys' school. Repton School, Repton became coed in the 1970s. Rugby School, Rugby became coed in 1992. Ryhope Grammar School, Ryhope became coed in 1969 and closed in 1988. Saint George Catholic College, Swaythling became a boys' school in the 1970s and returned to coed in 2013. Sedbergh School, Sedbergh became coed in 2001. Shiplake College, Shiplake became coed in 2023. Shrewsbury School, Shrewsbury became coed in 2015. Solihull School, Solihull became coed in 2005. Stamford School, Stamford became coed in 2023. St Columba's College, St Albans became coed in 2020. St George's School became a girls' school in 1904. St John's School, Leatherhead became coed in 2012. St Peter's School, York became coed in 1987. Temple Grove School, Heron's Ghyll became coed in 1984 and closed in 2005. Wellington College, Crowthorne became coed in 2005. Wixenford School, Wokingham (1869-1934). Worth School, Turners Hill became coed in 2008.
Merged The Cedars School, Upper Norwood merged with The Laurels School to become Fidelis College in 2025. Central Technology College, Gloucester merged with Bishop's College to become Gloucester Academy in 2006. Chatham House Grammar School, Ramsgate merged with Clarendon House Grammar School to become the Chatham & Clarendon Grammar School in 2011. Chichester High School for Boys, Chichester merged with Chichester High School for Girls to become Chichester High School in 2016. Crest Boys' Academy, Neasden merged with Crest Girls' Academy to become E-ACT Crest Academy in 2014. Friern Barnet Grammar School, Friern Barnet merged into the Dwight School London in 1995. Hawtreys Preparatory School, Slough merged into Cheam School in 1994. Kitwood Boys School, Boston merged with the Kitwood Girls' School to become Haven High Academy in 1992. Littlemoss High School, Littlemoss merged with Droylsden School, Mathematics and Computing College for Girls to become the Droylsden Academy in 2009. Manchester Central Grammar School/High School for Boys, Manchester merged into the coed Manchester Academy in 1967. Richmond Boys School, Halesowen merged with the Walton Girls School to become Windsor High School, Halesowen in 1985.